1. Field of the Invention
The current invention relates generally to the production of nitride based heterostructure devices. In particular, the present invention generally relates to nitride based heterostructures having a silicon dioxide layer for controlling the reverse leakage of current.
2. Background Art
Gallium-Nitride (GaN) based Metal Semiconductor Metal (MSM) devices for visible-blind ultraviolet detection may have reverse leakage current values of about 1×10−5 A-cm−2 (at −5 V) for interlaced electrode geometry MSM detectors. While GaN based transparent Schottky barrier detectors have a very sharp visible-blind cutoff and responsivity values as high as about 0.18 A/W, these devices have reverse leakage currents of approximately 1×10−6 A-cm−2.
Additionally, AlGaN/GaN Heterostructure Field Effect Transistors (HFETs) may have applications in microwave and optical communication systems. GaN-based Metal Insulator Field Effect Transistors (MISFETs) using i-GaN, i-AlGaN/GaN and Si3N4 as the gate insulator have been attempted. While these devices were operational, they exhibited a current-voltage characteristic collapse at high drain biases due to a large density of interface states. GaN-based Metal Oxide Semiconductor Field Effect Transistors (MOSFETs) using Ga2O3 and Gd2O3 oxides for the gate insulator have also been created. However, these devices exhibited a much smaller transconductance than conventional GaN-based High Electron Mobility Transistors.
Therefore, there exists a need for nitride based semiconductor devices having substantially lower reverse leakage currents and performance characteristics comparable or better than conventional devices in all other respects.